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How do write IF ELSE statement in a MySQL query
How do I write an IF ELSE statement in a MySQL query?
5 Answers
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What is cardinality in MySQL?
What is cardinality in MySQL? Please explain in simple, non-technical language.
8 Answers
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What's the difference between using INDEX vs KEY in MySQL?
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When looking at table info in the latest version of SQLYog it shows KEY keyname (column_name) when I created the table with INDEX keyname (column_name). The fact that it is a synonym explains it perfectly.
– crmpicco
Apr 2 '14 at 10:10
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凤姐当天使 徐小平胡海泉薛蛮子王刚怎么看？ - 资讯 - 清泛网 - 专注C/C++...
...变得更好，更强，更快，比如说滴滴，迅速崛起过程中，包括跟快的的合并过程，需要多少的资源组合，如果没有全社会力量总动员，这样一个巨大的合并，程维一个人是很难做成的。
管得少是一种态度，表达了投资人无限的...
Database, Table and Column Naming Conventions? [closed]
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I recommend checking out Microsoft's SQL Server sample databases:
https://github.com/Microsoft/sql-server-samples/releases/tag/adventureworks
The AdventureWorks sample uses a very clear and consistent naming convention that uses schema names for the organizatio...
Checking if a field contains a string
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https://docs.mongodb.com/manual/reference/sql-comparison/
http://php.net/manual/en/mongo.sqltomongo.php
MySQL
SELECT * FROM users WHERE username LIKE "%Son%"
MongoDB
db.users.find({username:/Son/})
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LINQ - Left Join, Group By, and Count
Let's say I have this SQL:
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Simple calculations for working with lat/lon and km distance?
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Why not use properly formulated geospatial queries???
Here is the SQL server reference page on the STContains geospatial function:
https://docs.microsoft.com/en-us/sql/t-sql/spatial-geography/stcontains-geography-data-type?view=sql-server-ver15
or if you do not waant to use box and radian...
Entity Framework .Remove() vs. .DeleteObject()
...tate is Deleted after that.) If you call SaveChanges afterwards EF sends a SQL DELETE statement to the database. If no referential constraints in the database are violated the entity will be deleted, otherwise an exception is thrown.
EntityCollection.Remove(childEntity) marks the relationship betwee...
MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes
I'm importing a MySQL dump and getting the following error.
14 Answers
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